CC My Excavate

-- My Excavate

-- DESCRIPTION:
--  This program will function in a similar manner to the default excavate program, but a little bit more efficiently.

--  When its inventory is full, it will attempt to place its items in chests behind and above where it started, attempting to place items in the next chest up
--  if the last one didn't accept one or more items. If it runs out of chests to place into and it still has items, those items will be discarded and when
--  its inventory is empty (aside from coal in slot 1), it will return to where it left off and continue.

-- When it is out of coal (don't use any weaker kind of fuel, please), it will attempt to pull more from a chest to the left of where it started. Because it is assumed
-- that you are using coal for fuel and a relatively low size argument

-- USAGE: myExcavate range [useBlacklist]
-- The range argument is self-explanatory.
-- The useBlacklist argument is optional, and if defined, item names defined in the blacklist (see "BLACKLIST ITEMS HERE" in the code below) will be discarded by the
-- turtle's inventory when its inventory is full or before it returns to deposit collected items.

-- pastebin get WgESfSf1 myExcavate
-- myExcavate 5 1

local argv = {...}

local item_blacklist = {}
local function bl_add(item_name)
    item_blacklist[item_name] = true
end

-- BLACKLIST ITEMS HERE

bl_add("minecraft:cobblestone")

-----------------------

local size = tonumber(argv[1])
local useBlacklist = false
if argv[2] then
    useBlacklist = true
end

local target_x = 1
local target_z = size
local target_y = -2

local curr_x = 1
local curr_z = size
local curr_y = 0

local x_direction = true -- true = +x, false = -x
local z_direction = false -- true = +z, false = -z

local FACE_AXIS_ARRAY = {"+z", "+x", "-z", "-x"}
local FACE_AXIS_MAP = {}
for f=1, 4 do
    FACE_AXIS_MAP[FACE_AXIS_ARRAY[f]] = f
end
local facing = 2

local function check_fuel()
    if turtle.getFuelLevel() < 80 then
        turtle.select(1)
        turtle.refuel(1)
    end
end

local function turn_towards(face)
    local face_index = FACE_AXIS_MAP[face]
    while not (facing == face_index) do
        local diff = facing - face_index
        if (diff == 1) or (diff == -3) then
            turtle.turnLeft()
            facing = facing - 1
        else
            turtle.turnRight()
            facing = facing + 1
        end
        if facing > 4 then
            facing = 1
        elseif facing < 1 then
            facing = 4
        end
    end
end

local function move_by(dist)
    while dist > 0 do
        check_fuel()
        if turtle.detect() then
            turtle.dig()
        end
        if turtle.forward() then
            dist = dist - 1
            if facing == 1 then
                curr_z = curr_z + 1
            elseif facing == 2 then
                curr_x = curr_x + 1
            elseif facing == 3 then
                curr_z = curr_z - 1
            elseif facing == 4 then
                curr_x = curr_x - 1
            end
        end
    end
end

local function discard_blacklist()
    if not useBlacklist then
        return
    end
    for s=2, 16 do
        local data = turtle.getItemDetail(s)
        if data and item_blacklist[data.name] then
            turtle.select(s)
            turtle.drop()
        end
    end
    turtle.select(1)
end

local function inventory_full()
    for s=2, 16 do
        if turtle.getItemCount(s) == 0 then
            return false
        end
    end
    return true
end

local function navigate_to_pos(x, y, z)
    if curr_x < x then
        turn_towards("+x")
        move_by(x - curr_x)
    elseif curr_x > x then
        turn_towards("-x")
        move_by(curr_x - x)
    end
    if curr_z < z then
        turn_towards("+z")
        move_by(z - curr_z)
    elseif curr_z > z then
        turn_towards("-z")
        move_by(curr_z - z)
    end
    while curr_y > y do
        if turtle.detectDown() then
            turtle.digDown()
        end
        check_fuel()
        if turtle.down() then
            curr_y = curr_y - 1
        end
    end
    while curr_y < y do
        if turtle.detectUp() then
            turtle.digUp()
        end
        check_fuel()
        if turtle.up() then
            curr_y = curr_y + 1
        end
    end
end

local function navigate_to_start()
    navigate_to_pos(1, 0, size)
end

local function deposit_items()
    discard_blacklist()
    navigate_to_start()
    turn_towards("-x")
    local deposit_failed = true
    while deposit_failed do
        deposit_failed = false
        for s=2, 16 do
            if turtle.getItemCount(s) > 0 then
                turtle.select(s)
                if not turtle.drop() then
                    deposit_failed = true
                end
            end
        end
        if deposit_failed then
            if turtle.detectUp() then
                turtle.digUp()
            end
            curr_y = curr_y + 1
            turtle.up()
        end
    end
end

local state = "mining" -- "mining" or "returning"
local min_y = 0

while not (turtle.detectDown() and (not turtle.digDown())) do
    min_y = min_y - 1
    curr_y = curr_y - 1
    check_fuel()
    turtle.down()
end
min_y = min_y + 4
navigate_to_start()

local running = true

while running do
    if state == "mining" then
        navigate_to_pos(target_x, target_y, target_z)
        if turtle.detectUp() then
            turtle.digUp()
        end
        if turtle.detectDown() then
            turtle.digDown()
        end
        if inventory_full() or (turtle.getItemCount(1) == 0) then
            state = "returning"
        end
        if x_direction then
            if curr_x < size then
                target_x = curr_x + 1
            elseif curr_x == size then
                if z_direction then
                    if curr_z == size then
                        if curr_y == min_y then
                            running = false
                        else
                            target_y = target_y - 3
                        end
                        z_direction = false
                    else
                        target_z = target_z + 1
                    end
                else
                    if curr_z == 1 then
                        if curr_y == min_y then
                            running = false
                        else
                            target_y = target_y - 3
                        end
                        z_direction = true
                    else
                        target_z = target_z - 1
                    end
                end
                x_direction = false
            end
        else
            if curr_x > 1 then
                target_x = curr_x - 1
            elseif curr_x == 1 then
                if z_direction then
                    if curr_z == size then
                        if curr_y == min_y then
                            running = false
                        else
                            target_y = target_y - 3
                        end
                        z_direction = false
                    else
                        target_z = target_z + 1
                    end
                else
                    if curr_z == 1 then
                        if curr_y == min_y then
                            running = false
                        else
                            target_y = target_y - 3
                        end
                        z_direction = true
                    else
                        target_z = target_z - 1
                    end
                end
                x_direction = true
            end
        end
        if target_y < min_y then
            target_y = min_y
        end
    elseif state == "returning" then
        deposit_items()
        navigate_to_start()
        turn_towards("+z")
        turtle.select(1)
        turtle.suck()
        state = "mining"
    end
end

deposit_items()
navigate_to_start()
turn_towards("+x")

print("Program Complete!")